Answer:
a. With 90% confidence the proportion of all Americans who favor the new Green initiative is between 0.6290 and 0.6948.
b. If the sample size is changed, the confidence interval changes as the standard error depends on sample size.
About 90% percent of these confidence intervals will contain the true population proportion of Americans who favor the Green initiative and about 10% percent will not contain the true population proportion.
Step-by-step explanation:
We have to calculate a 90% confidence interval for the proportion.
The sample proportion is p=0.6619.
The standard error of the proportion is:
The critical z-value for a 90% confidence interval is z=1.6449.
The margin of error (MOE) can be calculated as:
Then, the lower and upper bounds of the confidence interval are:
The 90% confidence interval for the population proportion is (0.6290, 0.6948).
Answer: The probability is about 0.2%.
The probability of flipping heads one time is 0.5, 50% or 1/2.
To flip heads 9 times in a row, we have to multiply 1/2 by itself 9 times.
(1/2)^9 = 1/512 or about 0.2%
It should only happen once every 512 times.
Answer: 
Step-by-step explanation:
-7+5 times -1+9
−7+5×−1+9
-7-5+9
−7−5+9
-12+9
−12+9
−3
Answer:
75°
Step-by-step explanation:
∠ESK is the supplement of ∠EDK, so is 100°. ∠ESD = 1/2·arc ED, so is 25°. Since ...
∠ESK = ∠ESD + ∠DSK
you have ...
100° = 25° + ∠DSK . . . . fill in known values
75° = ∠DSK . . . . . . . . . . subtract 25°
_____
Regarding opposite angles of an inscribed quadrilateral
Chord EK divides the 360° circle into two arc: major arc EDK and minor arc ESK. The sum of those arcs is 360°. Each of the inscribed angles that intercepts those arcs has half the measure of the arc. That is, ∠ESK intercepts arc EDK, so has half its measure. Likewise, ∠EDK intercepts arc ESK, so has half its measure. The sum of those opposite angles will be the sum of half the measures of the arcs, so half the sum of the arcs, or 1/2·360° = 180°.
This is why we can say ∠ESK is the supplement of ∠EDK.
